Kidney Week

Abstract: PUB151

Effect of Kidney Biopsy on Inpatient Outcomes in Hospitalized Patients with Rapidly Progressive Glomerulonephritis

Session Information

• Publication Only

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Velez-Oquendo, Gabriel, Northeast Georgia Health System Inc, Gainesville, Georgia, United States

Gabriel Velez-Oquendo, MD

• Siddiqi, Nabeel, Northeast Georgia Health System Inc, Gainesville, Georgia, United States

Nabeel Siddiqi, DO

• Aggarwal, Deepak K., Northeast Georgia Health System Inc, Gainesville, Georgia, United States

Deepak K. Aggarwal, MD

Background

Rapidly progressing glomerulonephritis (RPGN) often prompts consideration of renal biopsy during hospitalization, yet how inpatient kidney biopsy relates to mortality, length of stay (LOS), disposition, and cost in nationally representative data is incompletely described.

Methods

Data was obtained from the Healthcare Cost and Utilization Project National Inpatient Sample (NIS) 2016–2022 database to identify patients with RPGN using ICD-10 CM codes. Kidney biopsy during hospitalization was identifed by using ICD-10-PCS procedure codes. We assessed demographic and clinical predictors, and primary outcomes including in-hospital mortality, length of stay, disposition, and costs. Logistic regression was used to assess factors associated with in-hospital mortality and with receipt of kdiney biopsy; Linear regression was used for LOS.

Results

A total of 834 hospitalizations with RPGN were identified in the NIS database. Patients had a mean age of 61.2 years (SD 16.4) and were more likely to self-identify as White (66%) and female (54%). In adjusted multivariable models, kidney biopsy was not associated with higher in-hospital mortality (OR 0.74, p = 0.48) but was associated with LOS (5.6 additional days, p < 0.001), and higher total charges (charge ratio 2.05, p < 0.001). Moreover, patients with biopsy had higher odss of acute kidney injury (AKI) (OR 15.0, p < 0.001), a pattern that likely reflects diagnostic overlap with hospitalized RPGN rather than biopsy-attributable renal injury; dialysis use did not differ significantly (p = 0.33).

Conclusion

Out study showed that inpatient biopsy aligned with greater resource use and LOS, but no significant mortality difference. Although AKI odds were higher in patients who underwent biopsy, results are not causal inference about biopsy.

Inpatient Outcomes of Rapidly Progressive GN Stratified by Kidney Biopsy